15 Canis Majoris

Variable star in the constellation Canis Major Canis Major constellation map.svg center 280 right Red circle.svg 10 15 Canis Majoris 305 510 Location of 15 Canis Majoris (circled in red) J2000.0 Canis Major 06 53 32.907 −20 13 27.32 +4.794.84 B1IV -0.212 0.013 −0.96 β Cep 28.00 -5.46 0.16 +3.58 0.17 2.68 0.24 −3.02 12.8 1.2 3.89 0.20 20 12 6.8 1.2 20000 12000 7400 commas 26,100 1,200 commas EY CMa 15 CMa −20°1616 2532 50707 33092 2571 172520 9034 15+CMa 15 Canis Majoris is a variable star in the southern constellation of Canis Major, located roughly 1,200 light years away from the Sun. It has the variable star designation EY Canis Majoris; 15 Canis Majoris is the Flamsteed designation. The star is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of +4.8. It is moving away from the Earth with a heliocentric radial velocity of 28 km/s. thumb|left|A visual band light curve for EY Canis Majoris (1992) This is a B-type star with a stellar classification of B1 IV. Merle F. Walker discovered that 15 Canis Majoris is a variable star in 1955, and he published that discovery in 1956. It is classified as a Beta Cephei type variable star and its brightness varies from magnitude +4.79 down to +4.84 with a period of 0.18457 day hour out. The star has 12.8 times the mass of the Sun and 6.8 times the Sun's radius. It is radiating 20,000 times the luminosity of the Sun from its photosphere at an effective temperature of 26,100 K. References Walker Merle F. The Light Variability of 15 Canis Majoris Publications of the Astronomical Society of the Pacific April 1956 68 401 154–157 10.1086/126903 1956PASP...68..154W Heynderickx D. A photometric study of beta Cephei stars. I. Frequency analyses Astronomy & Astrophysics Supplement Series December 1992 96 207–254 1992A&AS...96..207H 15 CMa April 30, 2019 De Burgos A. Simón-Díaz S. Urbaneja M. A. Negueruela I. The IACOB project. IX. Building a modern empirical database of Galactic O9 - B9 supergiants: Sample selection, description, and completeness Astronomy and Astrophysics 2023 674 A212 10.1051/0004-6361/202346179 free 2305.00305 2023A&A...674A.212D XHIP: An extended hipparcos compilation Anderson E. Francis Ch. Astronomy Letters . 38 5 331 2012 2012AstL...38..331A 1108.4971 10.1134/S1063773712050015 119257644 Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system Gontcharov, G. A. 2006 Astronomy Letters 32 11 759–771 2006AstL...32..759G 10.1134/S1063773706110065 1606.08053 119231169 Mermilliod, J.-C. Compilation of Eggen's UBV data, transformed to UBV (unpublished) Catalogue of Eggen's UBV Data 1986 1986EgUBV........0M 1 Hubrig S. Briquet M. De Cat P. Schoeller M. Morel T. Ilyin I. New magnetic field measurements of beta Cephei stars and Slowly Pulsating B stars Astronomische Nachrichten 330 4 317 2009AN....330..317H 0902.1314 10.1002/asna.200811187 January 2009 17497112 Validation of the new Hipparcos reduction van Leeuwen F. Astronomy and Astrophysics 474 2 653–664 2007 0708.1752 2007A&A...474..653V 10.1051/0004-6361:20078357 free 18759600 Vizier catalog entry 1 Samus N. N. Kazarovets E. V. Durlevich O. V. Kireeva N. N. Pastukhova E. N. General Catalogue of Variable Stars 5.1 Astronomy Reports 2017 61 1 80–88 2017ARep...61...80S . 10.1134/S1063772917010085 125853869 Category:Beta Cephei variables Category:Canis Major BD-20 1616 Canis Majoris, 15 050707 033092 2571 Canis Majoris, EY Category:B1IV stars